Hydro-aero machine



G. H. CURTISS AND W. L. GILMORE.

HYDRO AERO MACHINE.

A PLICATION HLED APR- 26, I919.

52 him h 1, 9 ml onwm W M 2S HM, m 2 MHM. AVE IINHL WM m Y m B m P 3, ow w a a 8 1 H l3 ATTORNEY G. H. CURTISS AND W. L. GILMORE.

HYDRO AERO MACHINE.

APPLICATZOH FILED APRVZG, I919.

Patented Dec. 28, 1920.

2 SHEETS-SHEET 2.

INVENTOR: GLENN fiCurzrl-ss. WILLIAM LGILMORE.

H I ATTORNEY PATENT OFFICE.

UNITED STATES GLENN E. CURTISS AND WILLIAM L. GILMORE, OF GARDEN CITY, NEW YORK, ASSIGNORS, BY MESNE ASSIGNMENTS, 'IO CURTISS AEROPLANE AND MOTOR CORPORATION, OF BUFFALO, NEW YORK, A CORPORATION OF NEW' YORK.

- HYDRO-AERO mnennm Specification of Letters Patent. Patented Dec. 28, 1920.

Application filed April 26, 1919. Serial No. 292,833.

To all'whomit may concern:

Be it known that we, GLENN H. .CURTISS and WILLIAM L. GILMORE, citizens of the United States, residing at Garden City, in the county of Nassau and State of New York, have invented certain new and useful Improvements in Hydro-Aero Machines, of which the following is a specification.

Our invention relates to hydro-aero machines and more particularly to heavy duty commercial and military hydro-airplanes and'flying boats.

The demand at the present time for heavy duty aircraft is strong from both a commercial and military aspect. In the design of a commercial machine it is essential that the weight carrying capacity be developed to the maximum; thatv a high factor of safety be provided; that the cruising radius be large and wide; and that the flying crew be distributed about the machine for observation and communication purposes. In a military machine, and more particularly a coast patrol and aerial submarine chaser, it is not only essential that the above requisites be fulfilled but in addition it is essential that adequate armament, both defensive and offensive, be provided. All of these things are characteristic of our improved machine. The weight carrying capacity is obtained by the use of a plural powered motors and the design of the machine along ample lines. A high factor of safety is obtained by the adoption of an improved system of bracing and by the use of wiring and braces of the best of materials and of goodly size. The cruising radius is increased through the use of plural motors in conjunction with the installation of fuel tanks of unusually large size. Safety is assured in consequence ofthe sturdy construction and in consequence of the fact that the pilot is situated without the hull and in a position sufficiently elevated to enable him to see in all directions under all operating conditions. A machine thus characterized has a flying radius of approximately two thousand (2000) miles and but recently flew from the water with as many as fifty (50) passengers aboard. Moreover, it is entirely practical to fly the machine with two motors only, holding the third or additional motor in reserve. Such a machine is especially designed for trans-oceanic number of high-v of reference designate like or corresponding parts:

Figure 1 is a front end elevation of our improved hydro-aero machine showing the general arrangement of the various parts thereof; also the manner in which the wing structureis longitudinally braced;

Fig. 2 is a side elevation;

Fig. 3 is a plan view (partly broken away) and Fig. 4 is a section on the line 4'4 of Fig. 2.

In the embodiment of the invention selected for illustration three motors or power plants are provided. This number may be either increased or diminished as desired although it is preferred that at least one of the total number of motors be located centrally of the machine as viewed either from the front or rear. The supporting surfaces of which there are two (more may be provided if desired) are designated as 10 and 11. Each surface is made up of a number of connected panels and'the surface 10 (the upper) is preferably provided with a somewhat greater span. The supporting surfaces are interbraced by wing struts 12 and cross arranged brace wires 13, the latter being arranged in a manner common to the art. Longitudinally of its length however, the wing structure, which includes both supporting surfaces as well as the wing struts 12 and wires 13, is braced by wires termediately located between the end struts 12 and through such connection prevent deflection of the struts due to bending stresses set up in them in consequence of their unusual length. In addition to the bracing mentioned the wing structure is provided with' suitable brace wires 17 for the overhung end portions of the upper supporting surface.

The hull of the craft designated-as an entirety by the numeral 18 is constructed along lines differing somewhat from theordinary flying boat hull. At its forward end it is provided with a relatively sharp cut water bow 19 and at its stern end is provided with a knife-edge 20 Slightly inclined to'the'vertical. Intermediately of its ends the hull widens gradually to a maximum beam substantially amidships, from which point it tapers substantially uniformly aft to the stern. Unlike the conventional Curtiss flying boat hull, it is characterized by an absence of fin excrescences. The bottom of the hull is of course constructed in hydroplaning form. From the out water how 19 the bottom inclines rather sharply down: wardly and rearwardly and thence more horizontally to a point 21. At the point 21 a rearwardly facing step or shoulder is provided. 'Aft of the step the bottom inclines slightly upwardly and rearwardly to the stern although the distancefrom the step to the stern is considerably less than the distance from the bow to the step. In this way also the hull differs materially from the conventional design. In cross section the bottom of the hull is acutely V-shaped throughout substantially its full lengthfthe V being somewhat more acute at the'bow end of the hull than at the stern.

Within the hull the major items of useful load such as fuel, passengers, baggage, etc.', are carried. The space in the hull accorded the passengers and baggage is designated as 22. Preferably such space is distributed both fore and aft of the transverse vertical plane of the -center of gravity of the craft. The space provided for the fuel tanks is designated as 23. This space is preferably located in the vicinity of said transverse plane in the interest of longitudinal balance since the fuel constitutes the principal item of Variable orconsumable load. At the nose end of the hull a cockpit 24; is provided. Preferably this cockpit accommodates one or more of the flying crew, if a commercial machine, or if a military machine it is designed to accommodate suitable v ordnance such as a machine gun and also the gunner. From the cockpit space 24 it is apparent that an unobstructed observation range as well as an unobstructed gun fire range throughout a vertical arc of approximately 200 and a lateral arc of somewhat over 200.is provided.

In addition to the hull or flotation body 18 the machine is rovided with a central nacelle body 25. ithin' the forward end of this nacelle a motor is inclosed, which motor directly drives a propeller 26. Aft

of the motor and within the nacelle 25 cockpit space 27 is provided. This cockpit 27 is designed to house two or more of the fly- ;ingcrew, preferably the pilot and the motor mechanic. At each side of the center nacelle somewhat smaller nacelle bodies 28 are disposed. These smaller nacelles preferably are located symmetrically at opposite sides of the longitudinal vertical lane of the fore lated or controlled from the center nacelle.

The support for the motors or rather the nacelle bodies which contain the motors comprises engine bed beams (not shown) carried jointly by the wing struts 12 which interconnect the supporting surfaces 10 and 11. As shown in Fig. 1 the wing struts 12 which jointly constitute the motor supports extend parallel throughout their full length and are disposed in such adjacency as to effectually support the motors and the nacelles between the center section of the wing structure. The lower wing 11 at opposite sides of the hull is rigidly braced from beneath as indicated at 30. These braces extend diagonally inwardly from the foot of the inside supportin wing struts of the' side nacelles to the hul above its water line. The radiators for the motors may be supported as indicated, 71. 6., by the wing struts of the center section of the wing structure or if desired, they may be supported upon the engine beds in forward continuation of the nacelles.

The empennage of the craft, as in a hydro-airplane of the pusher type, is mounted at the .rear end of an outrigged tail structure 30'. It comprises superposed horizon,- tal stabilizing surfaces 31, superposed clevator flaps 32, laterally separated vertical stabilizing surfaces 33 and a plural number of vertical rudders 34. For ease of operation the elevator flaps 32 and the vertical rudders 34 are provided with overhangs. The tail structure 30'comprises three main spars and an intermediately located system of triangulated bracing. Two of the spars designated as 35 comprise separate spar sections, the sections in each instance being alined. Said spars 35 connect at their forward ends with the upper supporting surfaces 10 at points symmetrically at opposite sides of the longitudinal vertical plane of the fore and aft axis of the craft. From said points the spars converge slightly rearwardly and at their rear ends connect with the upper horizontal stabilizing surface 31. The third spar of the outrigged tail struc ture is' designated as 36. It is inclined slightly, rearwardly and upwardly from the control mechanism is much simplified due to of unequal size. The braces of the larger triangle are designated 38 and the braces of the smaller triangle are designated as 39. The braces 39 in reality strengthen the brace 38 since the smaller triangle is contained in the larger triangle as indicated in Fig. 4.

In addition to the triangulated bracing system the outrigged tail structure is braced throughout both transversely and longitudinally by a system of wires 40.

As indicated the pilot and motor mechanic are housed in the center nacelle 25. For this reason the control mechanism for the directional control surfaces 32 and 34 as well as the lateral control surfaces or ailerons 41, is inclosed in the cockpit 27 of the center nacelle. This is advantageous in that the pilot, by reason of his elevated position has a practically unobstructed range of vision ahead and beneath, which wide range of vision adds to the factor of safety of the machine. The practice heretofore in flying boats has been to either inclose or partly inclose the pilot and motor mechanic within the hull. The control mechanism may be of any well known character and is herein diagrammatically illustrated and designated as 42.

In addition to the three interwing nacelles a fourth nacelle 43 is mounted upon the top surface of the upper supporting surface 14 It is preferably centrally located and of substantially streamline form. In size it is much smaller than the remaining nacelles for in the preferred embodiment of the invention it is designed to accommodate but a single member of the flying crew. This nacelle also may be provided with a gun if the machine is a military machine or it may be provided with a radio outfit for communicating by wireless with distant points. From said nacelle the occupant has an unobstructed range of vision or gun fire as the case may be, in almost all directions.

The general arrangement above disclosed is the arrangement at this time considered best. In a commercial machine it segregates the flying crew from the passengers and at the same time places at least one member of the flying crew in positions enhancing safety in the operation of the machine. Moreover, by locating the pilot as indicated the arrangement of the control leads in carrying them from the control surfaces to the the fact that it is easy matter to extend the control leads directly into the.

nacelle, whereas to extend them as heretofore into the hull requires a large number of bends.

While we have described our invention in detail in its present preferred embod ment, it will be obvious to those skilled in the art after understanding our invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. We aim in the appended claims to cover all such modifiations and changes.

What is claimed is:

1. In a hydroaero machine, a flotation ,body, supporting surfaces extended intermediately across the flotation body, an empennage, and a support for the empennage comprising three spars, two of which extend rearwardly from one of the supporting surfaces and the other of which extends rearwardly from the flotation body, said two spars intermediately of their ends belng braced from beneath by braces extended d1- vergently upwardly from the flotation body.

2. In a hydroaero machine, a flotation body, supporting surfaces extended across the flotation body," an empennage, and a support for the empennage comprising three spars, two of which are relatively long and extend rearwardly from one of the supporting surfaces and the other of which is relatively short and extends rearwardly from the flotation body, the two relatively long spars and the flotation body being transversely interbraced.

3. In a hydroaero machine, a flotation body, supporting surfaces extended across the flotation body, an empennage, and a support for the empennage comprising three spars, two of which are relatively long and extend rearwardly from one of the supporting surfaces and the other of which isrelatively short and extends rearwardly from the flotation body, the two relatively long spars and .the flotation body being triangularly interbraced.

4. In a hydroaero machine, a flotation body, supporting surfaces extended intermediately across the flotation body, an .empennage, and a support for the empennage comprising a plurality of spars, two of which extend rearwardly from one of the supporting surfaces and one of which extends rearwardly from the flotation body, said two spars, intermediately of their ends and in substantially the transverse vertical plane of the stern end of the flotation body, being braced by braces extended respectively from the flotation body divergently upwardly for connection with said two spars and by a brace extended from one of the other of said two spars.

5. In a hydroaero machine, a flotation body, supporting surfaces extended intermediately across the flotation body, an empennage, and a support for the empennage support comprising three spars, two of which extend-rearwardly from one of the supporting surfaces and the other of which extends rearwardly from the flotation body, and atriangulated system of braces interconnecting said two spars and the stern end of the flotation body;

6. In a hydro-aero machine, a flotation body having space therein for fuel, baggage and other useful load, the body at its forward end being provided with space for occupancy by at least one of the flying crew, supporting surfaces extended intermediately across the body, a central nacelle body mounted between the supporting surfaces, space being provided within the nacelle for one-or more of the flying crew, side nacelles mounted at opposite sides of the central nacelle, the side nacelles being relatively small, a motor inclosed within each nacelle, a propeller for each motor, a nacelle mounted upon the top surface of the uppersupporting surface and also provided with space for occupancy by at least one of the flying crew, the occupant of thelast mentioned nacelle having an unobstructed range of vision laterally in all directions and anunobstructed range of vision vertically throughout an arc of approximately 200, an outrigged tail structure carried jointly by the supporting surfaces and the flotation body, the tail structure including spars extended I rearwardly respectively from the rear end of the flotation body and from the upper supporting surface at points symmetrically spaced laterally out from the longitudinal vertical plane of the fore and'aft axis of the craft, control surfaces mounted respectively at the rear end of the outrigged tail structure and at or near the ends of the support- -ing'surfaces, and mechanism inclosed within the central motor nacelle for operating the control surfaces and regulating the speed of the'several motors.

7. In a hydro-aero machine, a flotation body having space therein for fuel, baggage, passengers and other useful load, supporting surfaces extended intermediately across the body, motors mounted between the supporting surfaces, a propeller for each motor, an outrigged tail structure carried jointly by the supporting surfaces and the flotation body, the outrigged tail structure including spars triangularly arranged and connected respectively with the flotation body and with the upper supporting surface at points laterally removed from the longitudlnal vertical plane of the fore and aft axis of the craft,

the spars connecting with the supporting surfaces comprising alined spar sections having their points of connection with each other braced from beneath, control surfaces mounted respectively at the rear end of the outrigged tail structure and at or near the end of the supporting surfaces, and mechanism for operating the control surfaces and regulating the speed of the several motors.

8. In a hydro-aero machine, a flotation body, supporting surfaces extended intermediately across the body, aerial propelling means, an empennage, and a support for the empennage comprising an outrigged tail structure carried jointly by the supporting surfaces and the flotation body, said outrigged tail structure including two spars of equal length and connecting at their forward ends with the upper supporting surface at points laterally removed from the longitudinal vertical plane of the fore and aft axis of the craft and a relatively short spar connectedat its forward end to the stern end of the flotation body, the last mentioned spar being forwardly and downwardly inclined from its rear end and the first mentioned spars intermediately braced by a triangulated system of braces founded upon the flotation body at the point of connection of the inclined spar.

9. In a hydroaero machine, a flotation body, the body at its forward end being provided with space for occupancy by at least one of the flying crew, supporting surfaces extended intermediately across the body, a nacelle body mounted between the supporting, surfaces, space being provided within the nacelle for one or more of the flying crew, a nacelle mounted upon the top surface of the upper supporting surface, said last mentioned nacelle being likewise provided with space for occupancy by at least one of the flying crew, the occupant of the last mentioned nacelle having an unobstructed range of vision laterally in all directions and an unobstructed range of vision vertically throughout an arc of at least 200, a motor inclosed in the nacelle body first mentioned, an empennage supported above and to the rear of the flotation body, control mechanisms respectively for the motor and for the movable control surfaces of the em- 

